I love seeing new languages targeting the Lua runtime. I've been adding Lua scripting support to pretty much everything I make now. I recently made my SSE server programmable with Lua and it's extended the functionality far beyond what I would have had the patience and time to do myself. Highly recommend Lua with mlua-rs Rust bindings.
I would love to see a stripped back ML-style language that targets lua, just something like ocaml's type system and exhaustive pattern match right on top would be all I need. There have been a few attempts but nothing I know of that got usably far and is maintained.
There might be a way to get standard ML to output lua or something but I'm not that familiar with it. I think it would be an incredible fit for a third backend for gleam, but they say they aren't adding any more beyond erlang and js.
I think that LunarML [1] could fit this niche quite well. It's a StandardML compiler that targets Lua. I can't tell much more as I've only played with it a little and don't have much experience with ML languages in general, but it looks promising.
[0] https://tinysse.com
[1] https://github.com/benwilber/tinysse
[2] https://github.com/mlua-rs/mlua